Digital lighting technologies, i.e. illumination based on semiconductor light sources, such as light-emitting diodes (LEDs), offer a viable alternative to traditional fluorescent, HID, and incandescent lamps. Functional advantages and benefits of LEDs include high energy conversion and optical efficiency, durability, lower operating costs, and many others. Recent advances in LED technology have provided efficient and robust full-spectrum lighting sources that enable a variety of lighting effects in many applications. Some of the fixtures embodying these sources feature a lighting module, including one or more LEDs capable of producing different colors, e.g. red, green, and blue, as well as a processor for independently controlling the output of the LEDs in order to generate, for example, as discussed in detail in U.S. Pat. Nos. 6,016,038 and 6,211,626, incorporated herein by reference, a variety of colors and color-changing lighting effects.
One aesthetic lighting effect that can be recreated to varying degrees with LEDs is a candle lighting effect. Known LED lamps that attempt to accurately mimic a candle flame have been used for low-level background illumination. However, employing these types of LED devices for primary illumination, such as in, for example, a large chandelier, is relatively difficult, as the aggregate effect of such LED devices can appear as a fluctuation in total flux as opposed to a candle-like flickering. In addition, devices that rely on light-guide designs to mimic a candle flame tend to provide a sparkling effect rather than a flickering that one would expect from a candle flame.
Thus, there is a need in the art for an improved light-emitting device that provides a more accurate candle flickering effect that can maintain a total flux level for primary illumination purposes.